diff options
authorJames Bottomley <>2011-05-25 15:52:14 -0500
committerJames Bottomley <>2011-06-02 18:34:43 +0900
commite73e079bf128d68284efedeba1fbbc18d78610f9 (patch)
parent1fa7b6a29c61358cc2ca6f64cef4aa0e1a7ca74c (diff)
[SCSI] Fix oops caused by queue refcounting failure
In certain circumstances, we can get an oops from a torn down device. Most notably this is from CD roms trying to call scsi_ioctl. The root cause of the problem is the fact that after scsi_remove_device() has been called, the queue is fully torn down. This is actually wrong since the queue can be used until the sdev release function is called. Therefore, we add an extra reference to the queue which is released in sdev->release, so the queue always exists. Reported-by: Parag Warudkar <> Cc: Signed-off-by: James Bottomley <>
2 files changed, 2 insertions, 1 deletions
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 58584dc0724a..44e8ca398efa 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -297,7 +297,7 @@ static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
goto out;
+ blk_get_queue(sdev->request_queue);
sdev->request_queue->queuedata = sdev;
scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun);
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index e63912510fb9..e0bd3f790fca 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -322,6 +322,7 @@ static void scsi_device_dev_release_usercontext(struct work_struct *work)
+ blk_put_queue(sdev->request_queue);
/* NULL queue means the device can't be used */
sdev->request_queue = NULL;